The following reply was made to PR kern/45709; it has been noted by GNATS.
From: Taylor R Campbell <campbell+netbsd%mumble.net@localhost>
To: dieter roelants <dieter.NetBSD%pandora.be@localhost>
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
netbsd-bugs%netbsd.org@localhost, gnats-bugs%NetBSD.org@localhost
Subject: Re: kern/45709: tmpfs size went nuts
Date: Fri, 16 Dec 2011 22:59:31 +0000
Date: Thu, 15 Dec 2011 10:05:03 +0000 (UTC)
From: dieter roelants <dieter.NetBSD%pandora.be@localhost>
Could it be you didn't have enough free swap? I.e. the tmpfs file
system size seems to be capped by the amount of free memory.
Unlikely. I had two or three gigabytes of swap handy, and there was
only about a gigabyte of RAM in use at the time, plus a few dozens of
megabytes stored in the tmpfses. So there should have been four or
five gigabytes of memory free, not ten to twenty megabytes.